*Under what element in the DD do you place the EJB-QL statement?
<query>
...
<ejb-ql>your
ejb ql goes here</ejb-ql>
</query>
*And how do you use them in an entity bean method?
ejb ql are for finder and select methods, so you define the finder/select methods in the home intf/bean class first and add the ejb ql in the DD.
*Can you direcly run an EJB-QL statement from a bean method without using the DD?How ?
EJB-QL are instructions for the container to generate actual SQL (or other db specific queries) FOR THE finder/select methods you defined. You CANNOT execute EJB-QL directly.
* "CMR field is ALWAYS another entity bean's 'local' interface" - What if I have only 'remote' interfaces ? How do I relate beans then ?
No, you cannot use remote interfaces with CMR. If you really need remote interface for the ebean, you have to define both local and remote interfaces. You can define both at the same time.
Hope these help.